The present invention concerns a rotating bezel for a timepiece.
Known rotating bezel systems include an annular rotating bezel having a top surface and a bottom surface, with the top surface being the surface visible to the user. This bezel has notches or toothing on the bottom surface thereof. The rotating bezel system further includes a spring means. This spring means is inserted between the rotating bezel and the case band of the timepiece when the bezel is snap-fitted onto the case band of the timepiece. This spring means takes the form of a flat ring comprising leaves on the surface thereof facing the notches in the bezel. These leaves are arranged to tilt between 0° and 90° relative to the plane of the flat ring. The leaves have some elasticity so that the spring means acts on the rotating bezel to exert a vertical force. This vertical force has a tendency to push the bezel off the case band of the timepiece.
The leaves also serve to cooperate with the notches in the bezel. The leaves and catch are thus configured so that the bezel can only rotate in one direction. Generally, the bezel and the spring means are made of steel which has the advantage of being durable and inexpensive.
The same concept is used for making a bezel made of precious materials. However, the precious materials have unsuitable mechanical characteristics, such as for example low mechanical resistance. A snap-fit arrangement using precious materials thus has the drawback of being subject to rapid wear. A solution consists in making a snap fit arrangement which is added to the bezel. This arrangement makes it possible to have a bezel made of precious material but wherein the snap fit is accomplished using materials with a long service life. The drawback of this solution is that it requires a more complex manufacturing method since the snap-fit arrangement must be made separately and then fixed to the bottom surface of the bezel.
Further, rotating bezel systems have the drawback of being difficult to assemble to the case band since the spring means must be mounted first. The bezel is then assembled afterwards. Thus, not only is the assembly complex, but disassembly is virtually impossible and is liable to destroy the rotating bezel.
The whole forms a rotating bezel system of the prior art. These systems also have an unattractive operating noise which is bothersome for high end timepieces.